Apparent visual size under the downward vertical viewing was tested with the horizontal viewing conditions on the roof (outdoors) and on the corridor (indoors). Naive and immediate matching of the apparent size of the standard with comparison was requested binocularly. Mean matched size in the downward viewing remarkably approached to the law of visual angle, Deviations of judgments between Ss were larger in the downward viewing, Response dispositions, `attaining constancy' and `depending on the visual angle' were separated. The `attaining constancy' Ss showed almost equal effect of size constancy, and very small and constant deviation. Matches of `depending on the visual angle' Ss were inclined to accord with the peripheral variations.